Get Download URL

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnly, idempotent, and non-destructive. The description adds critical behavioral context: tokens are one-time use, the link expires after first download, and associated cloud files are cleaned up. It also notes that opening the URL triggers a download of 'merged.pdf' and source blobs are deleted. This goes well beyond the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is efficiently organized with a summary, args, returns, and notes. Every sentence adds value, and the most important information is front-loaded. No redundancy.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple single-parameter tool, the description fully covers preconditions, behavior, return format, and side effects. Even without an output schema, it outlines the return JSON. Complete and self-sufficient.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% with a well-described token parameter. The description reinforces the source ('from the merge response') and one-time nature, adding context not present in the schema. Slight value beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description opens with a specific verb+resource: 'Build a one-time download URL for a merged PDF.' This clearly distinguishes it from sibling tools (merge, upload, remove) and states exactly what the tool does.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly states the prerequisite: 'The token is returned by pdf_merger_merge.' This tells the agent when to use the tool, though it does not explain exclusions or when not to use it. The context is clear enough for correct deployment.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.